The Challenge.
NUTEC was recently engaged by a gas processing company to provide high temperature insulation for a flare chamber.
Some of the challenges for similar applications are that flare chambers are sited outside and are continually subject to all types of weather exposure.
Another challenge is that flares can be intermittent, meaning they oscillate rapidly between being off and on, full-heat to no-heat very quickly. Therefore, the refractory system within the flare is subject to thermal shock due to the repeated start-up/shutdown process. The insulation must be able to withstand such rapid and repeated temperature changes, and be of the right high heat insulation specifications to insulate the gas flares.
The actual fastening of the insulation needed to be considered for this project too, because the diameter of the flare made for a tight install and internal anchoring for the insulation wasn’t a good option.
Solution & Product Selection.
NUTEC’s MaxBlock 2600 ceramic fiber insulation modules and MaxWool 2600 ceramic fiber blankets are rated for applications up to 2,600°F (1,425°C).
Given the repetitive nature of the application and the critical safety role flares play in a petrochemical complex, this high-performance grade of product was specified. It can stand up to both the thermal shock, and the continual weather exposure demanded by the nature of this application.
For fastening insulation, NUTEC offers a variety of attachment options; each with its own design that best suits any particular application. In this case NUTEC’s H-Anchor system was selected for use. This system utilizes MaxBlock ceramic fiber modules, and does not have any internal anchoring hardware.
Fig. 1 MaxBlock 2600 ceramic fiber modules lining with H-Anchor System
The H-Anchors are pushed into the MaxBlock module and then welded in place on to the flare casing. The next module is then fixed to the protruding sides of the previously welded H-Anchor and the process repeats itself for the entire ring/row of modules.
Folded batten strips were then used between each ring of modules as a gasket and to seal against any potential openings in the lining. Other refractory options for this application can have performance issues due to weather exposure (layered blanket construction) and/or thermal shock (traditional hard refractories).
Results & Benefits.
NUTEC’s tailor-made solution afforded the following customer benefits:
Thermal Shock Resistance. The low mass of the MaxWool products makes them completely immune to thermal shock. The flare operators do not need to consider potential damage to the refractory system due to rapid start-up/shutdown of the flare – something which is often required.
Refractory Weight. Relative to a traditional castable refractory, the weight of a MaxBlock lining system is much less, resulting in potentially reduced structural steel requirement, and easier handling during erection.
Installation. The H-Anchor system provides flexibility for the installer when working in tight spaces. Since there are no internal module anchors, the MaxBlock modules can be easily trimmed / cut as required to fit lining channels for items such as air nozzles, etc.